Introduction

Atopic dermatitis (AD) or eczema is a chronic, relapsing form of skin inflammation that is attributable to multiple pathogenic, genetic, and environmental factors, as well as a dysfunctional epidermal barrier. Immune responses involved in AD culminate in dry skin, pruritus, and IgE mediated sensitization to food and environmental allergens.1 An improved understanding of crucial skin barrier defenses and the inflammatory cascade that drives disease activities has led clinicians to reassess conventional approaches to treatment and recognize emollients for their therapeutic potential. Accordingly, emollient-based moisturizers and cleansers have been established as essential adjuvants for successful AD management.

Background

AD is very common.

Prevalence is estimated at 15%-30% in children and 2%-10% in adults.2

In 85% of AD-afflicted children, onset of disease occurs before the age of 5 years.3

Up to 70% of children experience a spontaneous remission before adolescence.4

AD is associated with a marked decrease in skin barrier function due to endogenou factors.

Increasing evidence implicates one of the primary causes of AD as a genetic defect in the epidermis that permits the infiltration of allergens, environmental irritants, and microbes, thus inducing inflammatory responses.5

A defective skin barrier prohibits the necessary levels of antimicrobial peptides to form in the epidermis in order to protect against infectious agents, such as Staphylococcus aureus (S. aureus).

The Role of Moisturizers in Optimal AD Management

A persistent feature of AD is dry skin that is caused by a combination of intrinsic disease mechanisms and hyperreactivity to exogenous factors. Some treatments for AD can further exacerbate xerosis, itching, and irritation. Such external insults on an already impaired skin barrier drive the dry skin cycle and leave skin vulnerable to microbial infections. For these reasons, maintaining hydration and restoring epidermal barrier defenses provide the rationale for moisturization therapy.

What are Moisturizers?

Moisturizers are composed of a combination of key ingredients that are categorized as emollients, humectants, and occlusives, which work synergistically to enhance hydration and barrier function.

A randomized controlled study showed that well-designed formulations incorporating these constituents can improve the epidermal barrier function and increase skin hydration levels; however, the effects are determined by individual product composition.6,7

How do Moisturizers Work?

The mechanism of action of emollients may be elucidated as a role substitution by lipid ingredients, which take on the functions of naturally occurring lipids that are either absent or impaired in eczematous skin.

Treatment of the skin with moisturizers can repair the skin barrier, increase water content, reduce transepidermal water loss (TEWL), and restore the lipid barriers' ability to attract, retain, and redistribute water.

Maximum effects are derived from prophylactic and frequent use.

Moisturizers maintain hydration in the skin by slowing TEWL. In doing so, they help dry and/or aging skin to improve its structural integrity, appearance, and tactile properties.

By covering tiny fissures in the skin and providing an occlusive protective film over the stratum corneum (SC), moisturizers restore the epidermal barrier and reduce the penetrability of allergens and irritants.

Moisturizers Demonstrate Adjuvant Properties

Regimented moisturization has become standard adjunctive AD therapy by serving as a foundation to support pharmacologic measures, reducing the need for topical corticosteroids and calcineurin inhibitors, and mitigating the side-effects from medications.

During flares, OTC combination preparations containing a moisturizer with a topical corticosteroid (e.g., clobetasone and hydrocortisone) are helpful to control inflammation and restore the skin barrier.

Mild Skin Cleansers

The regular use of mild cleansers is an important aspect of optimal AD management. Not only is cleansing an essential part of basic hygiene, but it also removes dirt, sweat, bacteria, and exfoliated cells, which prepares the skin to receive topical medications and improves drug absorption.

AD lesions are commonly colonized with S. aureus. Routine cleansing can enhance antimicrobial activity against S. aureus and decrease the chances of infection.

Care must be taken to minimize any further weakening of the SC barrier during cleansing. The use of improper techniques and unsuitable cleansing agents on the face or body can initiate flares or exacerbate AD.

The use of anionic detergents (i.e., soaps) can alter the pH of skin, resulting in increased sensitivity to irritants and conditions that can promote bacterial proliferation.10

While removing excess sebum, cleansers can also inadvertently damage intercellular lipids, which can lead to further impairment of the barrier function and cause dry skin.

Cleansers that are suitable for eczematous skin are generally based on mild synthetic surfactants that cause minimal barrier disturbances.

Non-ionic surface-acting agents (e.g., silicone and polysorbate) are less likely to cause irritation and are pH-compatible with the skin.

Using the 4 Rs of AD Management

The best practice management of AD must include patient education. Pharmacists are encouraged to provide verbal and written information on AD and selected treatments, as well as practical demonstrations of proper administration. Remembering the 4 Rs can help to simplify the multi-layered approach for management.

Recognize

Recognize and diagnose the condition promptly in order for treatment to be initiated.

AD patients have a predisposition for developing other atopic conditions, such as asthma and allergic rhinitis.1

Encourage patients to maintain a diary to track foods eaten, flares, and the use of medications, moisturizers, and cleansers, which can guide therapeutic decision-making.

Conclusion

Due to the chronicity of AD, as well as multiple factors contributing to its etiology, successful management requires a multipronged approach that includes lifestyle modifications, adaptations to skin care practices, and medical intervention. Although topical corticosteroids are firmly established as the cornerstone therapy, long-term and overuse are associated with skin atrophy and adverse systemic effects. The combination of moisturizers with topical steroids can have a significant steroid-sparing effect, especially in children with mild-to-moderate AD. A therapeutic approach that incorporates patient education and emollient therapy can complement pharmacologic measures to extend periods of remission and significantly lessen the disease burden.